UTILIZATION OF TRANSESOPHAGEAL ECHOCARDIOGRAPHY IN INFECTIVE ENDOCARDITIS DIAGNOSIS: A SINGLE CENTRE EXPERIENCE

Echocardiography plays a key role in the diagnosis of infective endocarditis (IE). Although transesophageal echocardiography (TEE) has a higher sensitivity in identifying the presence of vegetations than transthoracic echocardiogram (TTE), it is a more invasive investigation with higher risk to the patient and higher cost to the healthcare system. Owing to a high prevalence of intravenous drug use (IVDU), Saskatchewan has a large number of suspected IE cases. The American Society of Echocardiography (ASE) and the European Society of Cardiology (ESC) have published recommendations regarding the appropriate use of TEE. The objective of this study is to evaluate the utilization of TEE in Regina, Saskatchewan, in the diagnosis of IE.

Patients aged ≥ 18 who received a TEE for the diagnosis of IE from January 1 to December 31, 2019 were identified. A retrospective chart review collected demographic and clinical information, as well as clinical outcomes. Primary outcome included the percentage of TEEs that complied with ASE and ESC recommendations. Factors associated with the inappropriate use of TEE were identified. Data analyses were carried out using Excel and IBM SPSS version 22. 204 admissions of 188 patients involved a TEE performed for the diagnosis of IE within the study period. The mean age was 53 ±17 years, with 41% females. 41.4% of patients had a history of active or past IVDU, 11.8% had prosthetic valves, and 9.8% had intracardiac devices. TEE confirmed the presence of a vegetation in 24.5% of cases. 13.2% of patients died during the same admission, and 33.3% died within 1-year of discharge. 30-day readmission rate was 26.0%. Only 30.9% of TEEs were appropriately used. Two criteria emerged as common reasons for inappropriately used TEEs. 46.6% of TEEs were performed without a prior TTE. 31.9% of TEEs were ordered for patients with a low pre-test probability in the absence of positive blood culture. Patients with a history of active or past IVDU was associated with more inappropriately used TEEs (74.4% vs. 61.2%, p= 0.046).

Patients who undergo TEE for the diagnosis of IE represent a high-risk population, with a high prevalence of IVDU, and high readmission and mortality rates. Only a small proportion of TEEs were appropriately used. Clinician education and a more protocolized approach towards the use of TEE in IE diagnosis may help reduce inappropriate usage.